Automatic furnace-grate.



(I. A. HORN.

AUIOMATIC FURNACE GRATE APPLlCATlQN FILED JUNEZ. 1917- Patented July 9,1918.

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C. A HORN.

AUTOMATIC FURNACE GRATE,

' APPLICAHON FILED JUNE 2. 1917. I 1,271,710. Patented July.9,1918.

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mix cam C.'A. HORN. AUTOMATIC FURNACE GRATE. APPLICATION FILED JUN E 2.I917.

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C. A. HORN.

AUTOMATIC FURNACE GRATE. APPLICATION FILED JUNE 2.1917.

Patented July 9, 1918.

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C.- A. HORN.

AUTOMATIC FURNACE, GRATE.

APPLICATION FILED JUNE 2. I9I?- Patented July 9 1918.

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UNETED @ATENT l FFEQE,

CHARLES A. HORN, OF NEW YORK, N. Y., ASSIGNOB OF ONE-FOURTH T0 1V.EVERET. BUNDLE, OF EAST ORANGE, NEW JERSEY, AND ONE-FOURTH TO HAROLD E.LOM- BARID, 0F BLOOMFIELD, NEW JERSEY.

AUTOMATIC FURNAGE-GBATE.

Specification of Letters Patent.

Application filed June 2, 1917. Serial No. 172,416.

To alt whom it may concern:

Be it known that 1, CHARLES A.\TIORN, a subject of the German Emperor,residing at Voodhaven, in the borough and county of Queens, city andState of New York, have invented certain'new and useful Improvements inAutomatic Furnace- Grates, of

which the following is a full, clear, and

exact description.

This invention relates to furnace grates, and 1ts chief object is toprovide a grate adapted to burn any and all kinds and gradesof coal,bituminous or anthracite, at. will. Another object is to provide a selfstfiing grate capable of stoking the fuel over the surface of the gratein an effective man- :ner, and, if desired, at a rate diminishingfromfront to back for the purpose of keepstances. Another object is toprovide an automatic grate which will discharge the ash, clinkers, andother refuse, without the use of water-backs and special dump-plates orthe like. Still another object is to provide an automatic grate whichwill agitate the fuel bed, thereby facilitating the passage of air andpreventing the formation of a cindercrust, which latter,.as is wellknown, is apt to confine the heat to such an extent as to cause injuryto the gratetops. To these and other ends the invention consists in thenovel features of construction and combinations of elements hereinafterdescribed.

In carrying out the invention in the preferred manner I provide a seriesof parallel rock shafts extending acrossthe'grate area, the series beinginclined downwardly at a suitable angle from front to back, that is,from the intake end of the grate to the rear or discharge end. Eachrockshaft carries a carrier-bar (on which the' grate-tops are mounted)and each bar is so arranged as to lie normally over the rockshaftimmediately in front. Each rockshaft also carries one or more deviceswhich, when the shafts are rocked in the proper direction, can lift thesuperposed carrier-bars and move the same toward the rear, therebyraising the fuel bed and moving "it to the rear. The mechanism forrocking the shafts is constructed to cause the carrier-bars (and, ofcourse, the grate- .t'ops thereon) to return to normal position insuccession, from front to rear.

the carrier-bar at the front first swings back, then thesecond from thefront, and so on. By this method the fuel bed is not permitted to fallback, bodily, to or nearly to, its

former position. Instead, the grate-tops slip back under the fuel,leaving theentire -bed in practicallv the position to which it was'movedby the simultaneous movement ofthe grate-tops. In short, the grate-topsreturn to home position like a receding wave from front to rear. As thewave travels a like wavetraverse's the fuel bed, thereby agitating thefuel and breaking up the bed more or less. Atthe rear of the grate thedescribed rearward movement of the fuel bed projets its rear portion,composed of ash and other refuse, over the edge of the ashpit, thuspermitting the 'refuse to fall into the latter. Means ar 'alsqprovidedby which the stroke or extent of movement of any carrier-bar or bars canbe varied. For

example, the stroke may diminish from frontto rear, so that thefuel-travel will be less rapid at the back. In this way t is easy tothicken the fuel bed toward the rear of the grate, to compensate for theconsumption of the fuel; it being readily understood that with a uniformtravel the amount of unconsumed fuel at the rear would be much less thanat the front: x

The embodiment thus briefly outlined is illustrated vin the annexeddrawings, in which- Figure l is a vertical longitudinal section on theplaneof line 1-1 in Fig. 2, looking in the direction of the arrows.

Fig. 2 is a plan view of the grate, with parts broken away and with mostof the That is,

Patented 51113 9, 1918.

bottom of the fuel hopper. Referring to the drawings, chiefly Fig. 1,

grate-tops removed to show theunderlying parts. 7

Fig. '3 is a front view of the furnace, showing the external parts ofthe grate Operating mechanism.

Fig. 4: is a detail plan View, showing por-J tions of several grate-topcarrier-bars and such-parts of the actuating mechanism as areimm'ediately connected therewith. This figure also shows a number of thegrate-tops in place on their respective carrier-bars. Fig.5 is a detailsection illustrating the movemntof the carrier-bars and the grate topsthereon.

carrier-bars, for example giving the rear carrier-bars less throw thanthose at the front. v

Fig. 7 is a detail sectional ,view, on the same plane as Fig. 1,illustrat ng the function of the means for determining the diiferentialthrow of the carriage-bars.

Fig. 8 is a detail cross section of several grate-tops, on the planeindicated by the line 8 in Fig. 5, illustrating the method of spacingthe grate-tops apart for the passage of air between them to the fuelabove. In this,

Fig. 11 is a detail perspective view of one of the spacers or spacingsaddles used between the grate-tops to space the same apart on thecarrier-bars.

Fig. 12 is a detailed plan view of one end of the sliding grid-valve orgate used in the 10 designates the fire or combustion chamber of thefurnace, having a roof 11 and at its' front, just below theroof, a mouth12 for the introduction offuel. The fuel is supplied from a hopper 13extending across the combustion chamber above the mouth. The hopper maybe divided into several coinpartments by walls 14: which, being integralwith or firmly connected to the vertical rear wall and inclined frontwall of the hopper,

aid the latter wall in resisting outwardly or downwardly exertedstresses, as do also the fins 15 on the outside. The bottom of thehopper is formed with a plurality of parallel slots 16 extendinglongitudinally of the furnace, and above the hopper bottom is atransversely sliding grid 17 (Fig. 12) having similar slots 18. Then thegrid slots,

are in registry with the hopper slots 16 the fuel can pass downwardlyupon the horizontal guide-plate 19," The grid is provided Fig. 6 is adetail view of one form of device for differentiating the throw of theat one end with an actuating bar 20 for connection with any suitablemeans, (not shown), actuated by hand or by power, to

shift the grid back and forth continuously or at proper intervals. Ifdesired the grid can be provided with agitating fingers, as 21, Figs. 7and 12, to agitate the fuel and so prevent arching over the grid.

, mental gears 24, by which it can bereci rocated longitudinally of thefurnace. he gears named are fixed ona transverse shaft- 25, which can berocked continuously or at suitable intervals by any convenientmechanism" for the purpose. Preferably this mechanism should be such aswill permit regulation of the speed of the pusher plate, and of theintervals between reciprocations thereof, within certain limits.Inasmuch as this mechanism is no part of the present invention it isdeemed unnecessary to illustrate the same herein.

The fuel falling from the hopper 13 upon the aide late 19 is pushedrearwardly ed the atter by the pusher plate 22) and upon thecoking-plate 26, where the fuel, being exposed to the heat of the fire,may undergo more or less coking. The guide-plate and the coking-plateare fixedly mounted on a transverse rockshaft 27. When thepusher plateis retracted, say about to the position; shown in Fig. 7 the shaft/27can be rocked counterclockwise by any convenient means, not shown,thereby lifting the coking-plate for kindling or inspection of the fireand for slicing, raking, or any "other work on the fuel bed that may berequired. The fire can also be observed through inspection doors 26, 26in the sides of the setting. At its rear the coking-plate rests on therear ortion of a transverse dead-plate 28 whic is provided with a grooveon its underside to fit down upon a transverse rib 29, thus permittingthe dead-plate to swin up and down on the rib as a pivot as the %rontedge of the dead-plate resting on the first transverse series ofgrate-tops, rises and falls.

A scraper 30, of'heavy sheet-metal bent to. inverted V-shape, is.mounted loosely on the pusher-plate 22 and in a transverse groove at thebottom of the hopper, to. prevent fine bits of fuel from working out onthe pusher plate. The transverse rockshafts 31', Figs. 1, '2, 4, and 5,are mounted in the longitudinal side and center frames 33. The shaftsare preferablyall in the same plane, which is infrom left to right asseen in Fig.1, Each shaft is provided with a plurality of arms orbrackets 34, extending forwardly, that-is,

clined downwardly from front to; rear, or Y toward the fuel-inlet end ofthe furnace,

and supported by roller-bearings 32, Fig. 5,

bearings 36, Fig. 5, a plurality of collars 37 having ownwardlyextending actuating arms 38, and forwardly extending lifting lugs orfingers 39, and the carrier-bars 35 immediately above are provided withdownwardly and forwardly extending fingers 40, resting on the the lugs39. As will readily lie-apparent from Fig. 5, the center of gravity ofeach carrier-bar and the associate brackets 34 and fingers 40 is infront of the shaft on which they are mounted, with the result that thefingers 40 rest by gravity on the lugs 39 and hence will follow themovements of the latter at all times.

The grate-tops 41 are preferably of elongated'form, rounded ed at theirends, and are provided at their front ends with downwardly .open notchesor recesses 42 to fit down loosely upon the upper edges 43 of thecarrier-bars 35. The grate-tops are arranged side by side on thecarrier-bars, forming a plurality of transverse series. The rear edge ofthe rearmost series, that is, the rear ends of the rearmost grate-tops,rest loosely on a transverse end frame 44, which forms the front edge ofthe passage 45 leading downwardly to the ashpit or hopper 46, while eachseries infront of the rearmost overlies-the series immediately in rear,as clearly shown in F ig. 1. In other words,-the grate-tops overlap fromfront to rear downwardly, but,

as indicated in Fig. 2, they are preferably in longitudinal alinement.The grate-tops 41 are of suflicient depth to form a well defined seriesof steps, as clearly shown in Fig. 1.

I As will be seen fromthe foregoing, my improved grate is composed,speaking generally, of a plurality of transverse gratesections or units.In the present embodiment of the invention each section or unit of thestoking grate includes a suitably mounted carrier-bar 35 and a pluralityof grate-tops 41 arranged side by side thereon.

For the purpose of actuating the arms 38 to raise the lugs 39 and soswing the carrier-; bars 35 and grate-tops 41 upwardly and rearwardly,said arms are pivotally connected to a series of actuating links or bars47 Figs. 1, 2, 3, 4 and 5, extending forwardly through a horizontalseries of slots in the furnace front-plate 48. At their front ends,outside of the front-plate, the links are provided with slidablyadjustable crossheads 49, resting on roller-bearing guide-rollers 50,(Fig. 7) mounted on a transverse shaft 51 supported by forwardlyextending brackets 52. In rear of the shaft 51 is a transverse camshaft53 having two series of cams 54 for cooperation with the aforesaidcrossheads to reciprocate the same and the links 47, there by actuatingthe grate-top carrier-bars in the manner described. In the embodimentillustrated the primary edges of all the cams, that is the edges thatfirst engage the crossheads, are in transverse alinement, but the camsof each series are of successively greater angular extent from theinnermost cams (54) outwardly, as clearly shown in Fig. 7, so that allthe crossheads will be advanced simultaneously but will be retracted insuccession as the cams pass, thereby causing the grate-top carrier barsto swing forwardly anddownwardly in succession from the front of thegrate to the rear; it being understood, of course, that the innercrossheads (Fig. 2) are connected to the first.

shaft 31, the second crossheads to the next shaft 31, and so on.

The cams 54 of each series can be made as separate parts, fixedindividually on the shaft in any convenient manner, but they are moreconveniently made integral with each other in the form of a singlecasting. The cam-shaft is rotated continuously by any convenient andsuitable mechanism, manual or power-driven, not shown, per

mitting the speed to be varied at will.

Above the links 47 and in rear of the crossheads 49 is a transverseshaft 55, equipped with two series of stroke-regulating arms or stops 56(Figs. 1 and 7), one series for each series or set of crossheads, eachstop being arranged to cooperate with, and limit the.

rearward movement of, its respective crosshead. The stops aresuccessively longer from the innermost outwardly, toward the sides ofthe furnace, as clearly indicated in Fig. 7. Hence when the stops areswung from the position shown in Fig. 1 to that shown in Fig. 7, or toany intermediate position, the rearward (rightward) movements of thecrossheads are successively less from the innermost crossheadsoutwardly, with the result that the upward and rearward movements of thegrate-tops 41, by which movements the fuel is fed over the grate to-'ward the rear or lower end of the same, are successively less from frontto rear. It is clear that the extent of rearward movement of eachcrosshead, and hence of the corresponding transverse series ofgrate-tops, depends, other conditions being the same, upon the radiallengths of the stops from the axis of the shaft 55, nd that thesedimensions can be varied as may be necessary or desirable to suit theconditions for which the particular furnace is designed. The stops ofeach series may be separate fromeach other and secured individually ontheir shaft, but they are more conveniently made integral with eachother in the form of a single castv as shown in Fig. 6.

I l8 shaft-55, carrying the stops 56, is adusted to the proper positionby any convenient mechan1sm, as for example a segmental Worm gear" 57,Fig. 2, fined on the shaft and meshing with a worm (not shown) on ashort shaft 58, Fig.- 2, which is mounted in a bracket 59, on the shafts53, 55, and is rotated by a handwheel 60. A. worm and:

Worm-gear mechanism is advantageous in that it not only enables accurateadjustment to he made by hand but also itself serves to securely holdthe shaft and stops in any pos sition of adjustment. 7

When the stops 56 are in the position shown in Fig. l thecrossheadsare'in transverse alinement, The revolving earns 54 will thereforeengage andadv'ance (toward the left) all the crossheacls simultaneouslyand,

hence will raise and move rearwardly all the gratetops 4-1simultaneously. ff, however, the stops are in, say, the position shownin Fig. 7, the innermost crcssheads will be advanced first and will bemoved the maximum distance, thereby raising and shifting rearwardly tothe maximum extent the forward'transverse series of grate-tops il. The

. next crossheads will he engaged by their respective cams'amoment laterand the extent of their forward (leftward) movement will hecorrespondingly less, with'a corre spending efi'ect upon the movement oftheir respective series of grate-tops. in like man-v the fuel rearwardlyover the grateat de creasing speed; In this way the consum tion of fuelcan be compensated for andt e thickness of the'fuel bed keptsubstantially uniform from front to rear. readily understood, the rateof decrease of y the vertical and horizontal motion of thefuel-feeding."wave can be varied at any time, whether there is a fire onthe grate or not, by adjusting the stops 56 as already de:

scribed.

An edect similar to that produced by the employment of the stops 56 asdescribed can he obtained by placing the crossheads 4:9-successivelyfarther out on the ends of the links, as will be readily understood.This differ- As will be ential mitted y the use of set-screws, as 49* tofasten the crossheads on the links. The chief purpose of having thecrossheads adjustable is to permit them to be lined up readily at anytime. A

The grate-top carrier-bar 35 at the extreme front of the grate is notrocked by cams 54, and hence the only movement imparted to the extremefront series of gratetops is a slightrocking, on the supporting edge ofthecarrier-bar, produced by the up ward movement of the next series ofgrate tops. This rocking of the. extreme front series of grate-topsgives a slight swinging movement in the dead plate 28, since the rearedge of the "latter rests on said series of %ositioning of thecrossheads is per grate-tops, which movement is imparted to thecoking-plate 26, the lower and rear edge of which rests on the rear ofthe dead plate.

Air for natural draft can be admitted to the air-chamber 61, Fig. 1,below the grate, by opening the inspection and cleaning doors 62 in *thefurnace front, Fig. 3. Air for mechanical draft is supplied throughducts 63, at each side of the aforesaid doors, by means of a fan orblower, notshown.

Thedistribution of airthrough the grate to the burning fuel is a highlyimportant 7 factor in conjunction with the varying rate of feed of thefuel over the grate. In the preferred embodiment 'of the invention theair that reaches the fuel bed from below comes through spaces betweenthe grate tops at the sides thereof. Preferably there are no other airopenings in the grate, and accordingly I prefer to have the'grate-topsnarrow in proportion to their length, so that air openings in thegrate-tops themselves will not be needed to keep the temperature of thegrate-tops down to a safe point. In' lieu of or in conjunction withbosses or projections (not shown) on the sides of the grate-tops tospace the same apart I prefer.

to employ removable spacers 64 (Figs. 8, 9 and 11) between thegrate-tops, in the form of inverted V-shaped members straddling theupper edges of the carrier-bars 35.

These spacers may all be of the same width or transverse thickness as inFig. 8, in

which case, as will be evident, the air spaces will beuniform throughoutthe grate; or

they can be of different widths, for example as in Fig. 9, thus, makingcorresponding dif 1 ferences in the areas of the air-openings. It

will therefore be seen that by using spacers of the proper widths theindividual airopenings can be given any area desired, from zero up toany reasonable limit, 80 also, by proper distribution of spacers '0different widths more air can be admitted at one part of the gratethanganother, thus giving any desired air-distribution In order toinsure proper positioning of the spacer on the carrier-bars, and toprevent displacement of the spacers, especially in cleaning the grate,kindling the fire, or in raking, slicing, or other hand work on thefire, the grate-tops are provided With lateral recesses 65, at thepoints Where they rest on the carrier-bars and the spacers are shaped tofit into these recesses, as clearly indicatedin Figs. 5, 8 and 9.

A certain amount of air can be admitted above the coking-plate 26, Figs.1 and 7, through a space 66, between the front of the roof 1'1 and thevertical rear wall of the fuel-hopper 13, which air will be pre-heatedby heat reflected from the roof before mixing with the gases distilledfrom the fuel.

The invention is shown embodied in a furnace for heating a steam boiler(indicated'by the water-tubes 66), but it is not limited to such use.

It is to be understood that the invention is not limited to theconstruction herein specifically illustrated and described, but can beembodied in other forms without departure from its spirit as defined bythe appended claims.

I claim:

1. In an automatic furnace-grate, in combination, a plurality oftransverse gratesections or units, and mechanism for giving the same insuccession from front to rear of the furnace a combined vertical andhorizontal movement of reciprocation, whereby the fuel-bearing surfaceof the grate is given a wave-like motion traveling from front to rear.

2. In an automatic furnace-grate, in combination, a series of transverseshafts, a transverse carrier-bar mounted on each shaft and extendingforwardly toward the next adjacent shaft, devices on each shaft forcooperating with the carrier-bar which is mounted on the next rearwardshaft to swing the same on the axis of its shaft, and

mechanism for actuating said devices.

3. In an automatic furnace-grate, in combination, a plurality oftransverse grate-sections or units, and means for simultaneously anduniformly moving the grate sections or units from an initial positionupwardly and toward the rear of the grate and causing the same to returnto initial position in succession from front to rear of the grate;

,4. In an automatic furnace grate, in combination, a plurality oftransverse gratesections or-nnits, pivotal supporting means for thegrate-sections or units permitting the same to be moved by gravity to alower and forward position, and mechanism for raising the grate-sectionsor units and movig the same in unison to anupper and rearward positionand then releasing them in succession from front to rear of the grate topermit their return by gravity to their lower and forward position.

5. In'an automatic furnace-grate, a grate- 4 mon warc ly therefrom, agrate-top carrier-ban the brackets, and a plurality of grate-topsmounted on the carrier-bar.

6; In an automatic furnace-grate, a gratesection or unit comprising atransverse sup porting shaft, a plurality of brackets mounted on theshaft and extending forwardly therefrom, a gratetop carrier-bar arrangedin front of the shaft and fixed on the brackets, and a plurality ofgrate-tops mounted on. the carrier-bar.

7. In an automatic furnace-grate, a grateseotion or unit comprising atransverse supporti 1g shaft, a plurality of brackets sited on the shaftand extending forarranged in front of the shaft and fixed on thebrackets, a plurality of grate-tops mounted on the carrier-bar, andmechanism for swinging the carrier-bar about the axis of the shaft.

8. In an automatic furnace-grate, in combination, a plurality oftransverse shafts, grate-top carrier-bars arranged to swing upon theaxes of the shaft each carrier-bar being arranged adjacent to and abovethe shaft next in front of its own shaft, actuating fingers fixed oneach carrier-bar and extending downwardly therefrom in front of theshafts over which the carrier-bars are arranged, actuating armsextending downwardly from the shafts and having lugs cooperating withthe said fingers to raise the same and thereby swing the carrier-barsupwardly and re'arwardly, and mechanism for rocking said arms on theaxes of their shafts.

9. In an automatic furnace-grate, in combination, a plurality oftransverse grate-sections or units; and mechanism for giving eachgrate-section a combined vertically and horizontally reciprocatorymovement; said mechanism including a plurality of forwardly extendingreciprocatory links connected to the grate-sections at their rear ends,and means for causing the links to be advanced simultaneously andretracted successively.

10. In anautornatic furnace-grate, in combination, a plurality oftransverse gratesections, or units each capable of combined verticallyand horizontally reciprocatory movement, a plurality of forwardlyextending reciprocatory links connected at their rear ends with therespective grate-sections to actuate the same, and a transverse seriesof cams adapted to normally advance the links simultaneously and permitthe same to he retracted in succession.

11. In an automatic furnace-grate, in combination, a plurality oftransverse grate-sections or units each capable of combined verticallyand horizontally reciprocatory movement, a plurality of forwardlyextending reciprocatory links connected at their rear ends with therespective grate sections to acto restrict the rearward movement of the,crossheads and links and hold the former: successively farther from theprimary edges of the cams whereby the links will be advanced. and thegratesections actuated in success-ion when the cams are operated.

12. In an automatic furnace-grate, in combination, a plurality oftransverse grate-sec tions or units each capable of combined verticallyand horizontally reciprocatory movement, a plurality of forwardlyextending reciprocatory links connected at their rear ends with therespective grate-sections to actuate the same, a .crosshead'fixed on theforward 7 end of each link the crossheads being in transversealinementwhen the links are in their rearmost positions, a plurality of cams ofsuccessively greater .angular extent but having their primary edges intransverse alinement to normally engage and advance all thecrossheads-simultaneously, aseries of stroke-limiting stops adapted. torestrict the rearward movements of the crossheads and hold the samesuccessively-farther from'the alined primary, edges of the cams, andmeans for shifting the stops into and out sively in the other direction.

afix my s gnature. 75

tive position.

of opera- 1 13. In an automatic furnace-grate, in combination, aplurality of forwardly and rear- Wardly movable transversegrate-sections or units, a plurality of forwardly extending linksconnected at their rear ends to the respeetive grate-sections to actuatethe same,

means for-causing the links to move for:

wardly and rearwardly, a shaft extending across-the links at thefront'thereof, and a plurality of stroke-limiting stops fixed on theshaft to limit the rearward movements thereof. a

' I 14. In an automatic furnace-grate, in con1- bination, a plurality ofmovable transverse grate-sections or units, a plurality of for- 'Wardlyextending actuating links connected at their rear ends to thegrate-sections a plurality of crossheads fixed on the front ends of thelinks, means cooperating with the crossheads to cause the same and thelinks tomove forwardly and rearwardly, and a plurality of guide-rollersunder the cross heads to support the same.

.15. In an automatic furnace grate, in combination, a plurality oftransverse=gate-sec tions'or units capable of combinedvertically andhorizontally reciprooatory movement, a plurality of cams, and apluralityof links connected with the grate-sections to actuate the same andhaving means to cooperate with the cams for actuation. thereby, saidcams andmeans'b'eing adapted to move the links simultaneously in onedirection and succes- In testimony whereof I LES A. HORN,

